Marine turbine.



K. AL QUlST I MARINE TURBlNE. APPLICATION FILED JAN.20, 1315.

1,153A?58 P atentedsept. 14, 1915.

Inventor: Kar! o l uisL, f I,

Him

' driven Tat full, 1 intermediate or cruising cents. I

KARL ALQUIST, OF SCHENEGTADY, NEW YORK, ASSIGNOR TO EENERAL ELECTRICCOMPANY, A CORPORATION OF NEW YORK.

MARINE TURBINE.

Specification of Letters Patent.

Patented Sept. 11a, 1915.

Application filed January 20, 1915. Serial a... 3,254.

To all whom it mag concern:

Be it known that I, IxAnL AL UIs'r, a

. subject of the King of Sweden and Norway,

residing at Schenectady, county of Schenectady, State of New York, haveinvented certain new and useful Improvements in Marine Turbines, ofwhich the following is a specification.

The present invention relates to turbines for propelling vessels, and inparticular to those intended for war vessels Which, for i the greaterpart of thetime, are operating .7 at cruising speed, but are at timesrequired to operate at.higher or maximum speeds.

The purpose of my invention is to provide an arrangement or grouping ofturblnes for propelling a vessel, and in particular one havingtwin'screws or propellers, which, by changing the number of turbin'es inservice and the manner in which they receive steam or other elasticmotive fluid, can be made to operate with hlgh economy at maximum,intermediate, and

cruising speeds.

-.F or a consideration of what I belleve to be novel and my invention,attention is ditem of turbine propulsion for vessels; Fig. 2

is a diagrammatic illustration of a main and a cruising turbine;' F 1g.3 1s a dlagrammatic detail view of the main and auxlhary .nozzles; Fig,4 is a detail view of a double seated valve for controlling theadmission of steam to the maln and cruising turbines, and Figs. 5 to 7are dlagrammatic views illustrating the flow of steam to the turbinesunder difierent operating conditions.

2 and 3 indicate twin main turbines for propelling the vessel at maximumspeed,

3 I While the turbine can be eachof which drives a propeller shaft 4:either directly or through speed reducing gearlng 5. The latterarrangement s prefl erable because the propellennfi can be- .driven atits nfost favorable effective speed, I made relatively small and lightand operated at a high and most "favorable. speed, thereby obtaining OOdeconomy of operation. :By arranging the gearing in the positionshownitis al- 'ways in. service whether, ,.the ship isibeing': the.auxiliary set of nozzles 16 in each main turbine is cut out pf service.They are, 116

turbine has a forward speed. I have not illustrated the gearing indetail because its specific constructionforms no part of the presentinvention. In other pending applications I have disclosed gearingsuitable for this purpose. The turbines operate on the impulse plan andare preferably of the Curtis type because of their high economy anddecreased weight and moderate speed for a given output. Each drivingelement 7, Fig. 2, comprising in the present instance one or more wheels8 having a plurality of rows of peripheral buckets and one or morewheels 9, each having a single row of peripheral buckets, said'wheelsbeing mounted on the shaft 10. In the rear end of each turbine casing islocated a reversing element 11 comprising one or more bucket wheelsmounted on the shaft 10. Both the forward driving and reversing elementsexhaust into condensers 12. The extracting capacity of turbine bucketsdepends roughly on the square of their speed. That is to say, if thebucket speed be decreased onehalf the energy range for equal extractingefficiency thereof will be reduced to about I one-fourth, hence theimportance of increasing the number of stages for reduced speedoperation,a feature which will be referred to later.

Each main turbine is provided with a set of nozzles 13 adapted in sizeand shape to .receive high pressure boiler steam from the supply main 14and convert a predetermined percentage of its pressure into velocity,which in turn is converted into useful Work by the rotating element, asis Well understood Between the various bucket wheels,

each in a'stage of its own, are stage nozzles 15 for converting pressureinto velocity and conveying steam between the stages in a manner Wellunderstood. Each turbine is also provided with an auxiliary or lOWpressure set of nozzles 16 adapted in shape and size to receiveexhauststeam from a cruising turb ne, to be described later, and convert apredetermlned percentage of 1ts pressure into velocity, Which in turn isconverted into useful work. by the rotating element. The

main and auxiliary nozzles receive their supplies ofsteam from separatechests, the purposefof which will be referred to later. When operatingat full speed and power however, in service for cruising speedconditions. For full and high intermediate speed conditions the mainadmission nozzles only are in service. The main turbines are designed togive their maximum economy at nearly full or full speed'of the ship.

Situated in line with the main turbines.

and preferably forward thereof to facilitate cutting the same into andout of service, are auxiliary or cruising turbines 17 and 18 that-areadapted to be connected to and disconnected from the main turbine shaftsby releasable clutch couplings 19 and 20. These turbines are providedwith bucket wheels of such diameter as to etlicient-ly extract energyfrom the steam at lower speeds of the ship. They may be uncoupled fromthe'main turbines when the'latter are operat-' predetermined percentageof pressure into 'separate auxiliary nozzles 1(3 of the main velocitywhich in turn is extracted by the buckets of the rotor. They exhaustinto the turbines and are adapted to extract only a portion of the totalenergy of tl, ie steam at any time. If the same'nozzles were used in themain turbine for boiler steam and also for exhaust steam fromthecruising turbine, whenever boiler steam was admitted to the chestsupplying saidnozzles it would also flow back into the shell of thecruising turbine and in thismanner subject it to very high stresses.This could be avoided by using a valve in the conduit between the twoshells but there would still be the danger of the operator neglecting toclose it which is avoided by my improved construction. Further it wouldrequire an additional operation which I avoid.. ()ne of thecruising-turbines is also provided with an auxiliary or low pressure setof nozzles 18, resembling the. other nozzles in general construction.which is put into service only for low speed cruising coiu'litions whenthe two turbines are seria ll y arranged as regards the passage ofsteam, as will appear later in connection, with Fig. 7. When the.cruising turbines are operating in seriesas regards the passage of steamt'l'ieuna-iir rim-lame are connected in parallel as regards the passageof steam; the various groups of admission and stage nozzles beingplroportioned in a manner well understood giye the desired tion thevalvef30 will shu .ofi' the flow of steam cruising tulrh ne 17 to mainwork division.

High pressure or boiler steam is admitted to the main turbines inparallel for high speed propulsion by the conduit ll subject to thecontrol of throttle valves 23 and 2*. High pressure or boiler steam isadmitted to the auxiliary or cruising turbines-by the conduit 14.subject to ,the control of the throttle valves 26 and 27. The exhauststeam from the cruising turbines 17 and 18 enters the main turbines Zand 3 by the conduits 2S and 29 subject to the control of valves 30 and31.- Valve 30 may with advantage be of the construction shownin Fig. 4c.The valve is' of the doubleseat type and is operated by the usual nutand screw 32, there being a hand wheel 33 on the valve spindle. When thevalve is raised all the steam passes to the main'turbine and whenlowered it all passes to the cruising turbine. By using a valve of thischaracter. one of the'exhaust pipes always remains open and thusprevents any abnormal rise of pressure in the shell of the cruisingturbine 17. It also enables me. to reduce the total number of the valvesrequired.

In Fig. 5 is shown diagrammatically the relation of parts for high speedoperation of the vessel, for example 25 to 30 knots. The cruisingturbines are mechanically disconnected from the main turbines by openingthe clutches 19 and 20 and all steam is shut off therefrom by closingthe supply valves 26 and 27. The auxiliary nozzles 16 ofthe mainturbines are also inactive and valves 3Q and 31 are shut. High pressuresteam is admitted to both turbines in parallel from the main 1l,'thethrottle valves 23 and 2t being open to the desired extent.

In Fig. 6 is shown diagrammatically the relation of parts for medium orintermediate speeds of the vessel. In this figure 'the main and cruisingturbines are operating together, the parts of the clutch couplings 19and 20 being united. lligh pressure steam is admitted in parallel to thestarboard and port I turbines, the exhaust from the cruising turbinespassing through the conduits 28 and 29 to auxiliary sets of nozzles 16into the main turbines. the latter exhausting into the condensers. Thisarrangement is adapted to operate at its best etliciency for anintermediate. speed of thevessel of, say 20 knots.

In Fig. 7 is shown diagrzumnat-ically the relationof parts for low speedor cruising operation of the vessel. Illthis figure the cruisingturbines are connected in series as regards the passage of steam. andthe two main turbines are connected in parallel as regards the passageof steam. both operating on the exhaust steam from the cruising tur--billes. This arrangement'is adapted for low ...speeds of the vessel, say12 to 16 knots for example. mUnaler this. condition of opera- Y beingsufficient for pressure nozzle 16 of the second main turbine 3. Underthese conditions the valve 31 occupies a mid position.

As an illustration of my invention, but not as a limitation thereof, thefollowing outputs and speeds may be considered as typical of theconditions for each propeller:

Propeller Horse revolutions Knots. power. per minute.

The illustration above given clearly shows the very great difference inshaft horse power between a vessel operating at maximum speed and thesame vessel operating at low or cruising speeds. It also makes apparentthe very great necessity of so arranging or combining the turbines indifierent ways or groups so that they can economically utilize themotive fluid at different speeds of the vessel. My improved arrangementcontemplates three principal speeds of the vessel-high, intermediate,and low, at which a high degree of economy in the use ofsteam or themotivefiuid is-efiected, these the great majority of cases. For speedsother than those specified I can resort to cutting nozzles out ofservice, as by the valves 36, especially for the main turbines, or bythrottling the supply of bines can be put steam. As a generalproposition the feature of cuttlng-nozzles into and out of service willbe limited to the high pressure portions of the installation andthrottling to the low pressure portions, although in some instanceseither or both modes of control may be employed.

The principal advantage of my improved arrangement resides in the factthat the vessel can be operated economically at the three speeds mostoften required, thereby.

increasing its radius of operation. This primary advantage is broughtabout by the fact that the main turbines with their main admissionnozzles can be designed to give their best efliciency at high speeds,that for inter-.

mediate speeds additional and efiicient turinto service so that agreater number of wheels or rows of buckets can be employed'whereby theywill have substantially the same total extraction efficiency, but

at a lower speed with a lower total steam are designed for,

.main turbines to mum speeds,

maximum,

speeds of the ship.

combination .,pr'opel the ship at maximum speed,rnam and volume. This isin part due to the use of auxiliary nozzles which are properly de thepassage'of steam and hence a lower speed of the vessel is obtained witha corresponding lower shaft speed and a decrease in total steam volumewithout substantialsacrifice in economy of operation.

By employing cruising turbines arranged in the manner described I reducethe losses when the vessel is operating at full speed because thecruising turbines do not form a dead load on the main turbines, and Imay further avoid the danger due to operating said turbines undergreater speeds than they and because of this turbines pf less expensiveconstruction may be used.

In accordance with the provisions of the patent statutes, I havedescribed the princlple of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof;but I desire to have it understood that the apparatus shown is onlyillustrative, and that the invention can be carried out by other means.

What I claim as new and desire to secure by Letters-Patent of the UnitedStates, is

1. In a system of combination of main turbines arranged to propel theship at maximum speed, cruising turbines arranged to cooperate with thepropel the *ship' atspeeds below the maximum, and means arranged toconnect the cruising turbines in series with the main turbines asregards the flow of steam for intermediate speed conditions and toconnect the cruising turbines serially as regards the flow of steam andto supply the exhaust therefrom to the main turbines in parallel forlower speeds of the ship.

2. In a system of ship propulsion, the

combination of propeller shafts, main 'turbines arranged to propel theship at maxispeed reducing gearing between the turbine and propellershafts, cruising turbines arranged to be connected to the main turbinesand cooperate therewith to propel theship at speeds below the releasablecouplings between the shafts of the main and cruising turbines, andmeans arranged to connect the cruising turbines in series with the mainturbines as regards the flow of. steam for intermediate ship propulsion,the.

speeds oftlre ship-and to connect the cruising turbines serially asregards the flow of steam and t6 supply the exhaust therefrom to themain turbines 3. In asystem ,of ship propulsion, the of main turbinesarranged to in parallel for weer are main turbines in parallel for lowerspeeds of the ship.

4:. In a twin screw system of ship propulsion, the combination of twinpropeller shafts, two main turbines for driving the ship at full speed,speed reducing gearing between each turbine and its correspondingpropeller shaft, two cruising turbines, releasable couplings forconnecting the shafts of the cruising turbines tothose of the mainturbines, and means'for connecting the cruising turbines in series asregards the flow of steam with the main turbines .for 'certain' speedsof the ship and for connecting them in series as regards the flow ofsteam and to exhaust into the main turbines for certain other speeds ofthe shin.

In a system of ship propulsion, the combination of propeller shafts,main turbines coupled thereto for propelling the ship at maximum speed,cruising turbines each having a separate casing and whose rotor iscoupled to the respective main turbine shaft for cruising speeds, all ofsaid turbines being provided with nozzles so proportioned as to give thedesired work division, meansfor connecting the cruising turbines to anddisconnecting them from the main turbines, conduit means for connectingeach cruising turbine in series with a main turbine and for connectingthe cruising turbines in series with each other as regards the flow ofmotive fluid and to exhaust into both main turbines, and valves in saidconduit means for' ,controlling the passage of motive fluidtherethrough.

Copms of this patent may be obtained for five cents each, by addressingWashington, D. 0.

6. In a system of ship propulsion, the combination of propeller shafts,condensing main turbines coupled thereto for propelling the ship atmaximum speed, cruising turbines having separate casings whose rotorsare in line with the shafts of the main turbine and are coupled theretofor low speeds only of the ship, all of said turbines being providedwith nozzles so proportioned as to give the desired work division,releasable couplings between the main and cruising turbines, conduitsfor admitting live steam to the main turbines for high speeds and to thecruising turbines for lower speeds, a conduit connecting the exhaust ofone cru1sing turbine with the inlet of another, conduits for connectingthe exhaust of the last named cruising turbine with the low pressurenozzles of the main turbines, and valve means controlling the passage ofsteam through the conduits. v

7. In a system .of ship propulsion, the combination of propeller shafts,condensing main turbines coupled thereto for propelling the ship atmaximum speed, main and auxihary nozzles for sald turbines, cruisingturbines having separate casings Whose rotors are coupled to the mainturbme shafts for' low speeds only of the ship, main nozzles for thecruising turbines, an auxiliary nozzle for, one of said turbines, thenozzles of all of said turbines being so proportioned as to give thedesired work division, releasable couplings between the main andcruising turbines, conduits admitting live steam to the turbines,aconduit for connecting the exhaust of one cruising turbine with theauxiliary nozzle 'of another \cruising turbine, conduits receiving theexhaust of the last named turbine and delivering it' to the auxiliarynozzles of-the main turbines, and valve means for controlling thepassage of steam through the conduits.

In witness whereof, I have hereunto set my hand this 13th day ofJanuary, 1915.

- KARL 'ALQUIST. Witnesses:

HELEN Onronn,

MARGARET 1*.Woonnnr.

the Commissioner of Fatents,

